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-rw-r--r--Documentation/ABI/testing/sysfs-bus-i2c-devices-bq32k7
-rw-r--r--Documentation/cgroup-v1/rdma.txt109
-rw-r--r--Documentation/cgroup-v2.txt103
-rw-r--r--Documentation/devicetree/bindings/rtc/armada-380-rtc.txt8
-rw-r--r--Documentation/devicetree/bindings/rtc/cortina,gemini.txt14
-rw-r--r--Documentation/devicetree/bindings/rtc/imxdi-rtc.txt5
-rw-r--r--Documentation/devicetree/bindings/rtc/maxim,ds3231.txt3
-rw-r--r--Documentation/devicetree/bindings/rtc/pcf8563.txt3
-rw-r--r--Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt27
-rw-r--r--Documentation/devicetree/bindings/rtc/sun6i-rtc.txt10
-rw-r--r--Documentation/static-keys.txt4
11 files changed, 279 insertions, 14 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-i2c-devices-bq32k b/Documentation/ABI/testing/sysfs-bus-i2c-devices-bq32k
new file mode 100644
index 000000000000..398b258fb770
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-i2c-devices-bq32k
@@ -0,0 +1,7 @@
+What: /sys/bus/i2c/devices/.../trickle_charge_bypass
+Date: Jan 2017
+KernelVersion: 4.11
+Contact: Enric Balletbo i Serra <eballetbo@gmail.com>
+Description: Attribute for enable/disable the trickle charge bypass
+ The trickle_charge_bypass attribute allows the userspace to
+ enable/disable the Trickle charge FET bypass.
diff --git a/Documentation/cgroup-v1/rdma.txt b/Documentation/cgroup-v1/rdma.txt
new file mode 100644
index 000000000000..af618171e0eb
--- /dev/null
+++ b/Documentation/cgroup-v1/rdma.txt
@@ -0,0 +1,109 @@
+ RDMA Controller
+ ----------------
+
+Contents
+--------
+
+1. Overview
+ 1-1. What is RDMA controller?
+ 1-2. Why RDMA controller needed?
+ 1-3. How is RDMA controller implemented?
+2. Usage Examples
+
+1. Overview
+
+1-1. What is RDMA controller?
+-----------------------------
+
+RDMA controller allows user to limit RDMA/IB specific resources that a given
+set of processes can use. These processes are grouped using RDMA controller.
+
+RDMA controller defines two resources which can be limited for processes of a
+cgroup.
+
+1-2. Why RDMA controller needed?
+--------------------------------
+
+Currently user space applications can easily take away all the rdma verb
+specific resources such as AH, CQ, QP, MR etc. Due to which other applications
+in other cgroup or kernel space ULPs may not even get chance to allocate any
+rdma resources. This can leads to service unavailability.
+
+Therefore RDMA controller is needed through which resource consumption
+of processes can be limited. Through this controller different rdma
+resources can be accounted.
+
+1-3. How is RDMA controller implemented?
+----------------------------------------
+
+RDMA cgroup allows limit configuration of resources. Rdma cgroup maintains
+resource accounting per cgroup, per device using resource pool structure.
+Each such resource pool is limited up to 64 resources in given resource pool
+by rdma cgroup, which can be extended later if required.
+
+This resource pool object is linked to the cgroup css. Typically there
+are 0 to 4 resource pool instances per cgroup, per device in most use cases.
+But nothing limits to have it more. At present hundreds of RDMA devices per
+single cgroup may not be handled optimally, however there is no
+known use case or requirement for such configuration either.
+
+Since RDMA resources can be allocated from any process and can be freed by any
+of the child processes which shares the address space, rdma resources are
+always owned by the creator cgroup css. This allows process migration from one
+to other cgroup without major complexity of transferring resource ownership;
+because such ownership is not really present due to shared nature of
+rdma resources. Linking resources around css also ensures that cgroups can be
+deleted after processes migrated. This allow progress migration as well with
+active resources, even though that is not a primary use case.
+
+Whenever RDMA resource charging occurs, owner rdma cgroup is returned to
+the caller. Same rdma cgroup should be passed while uncharging the resource.
+This also allows process migrated with active RDMA resource to charge
+to new owner cgroup for new resource. It also allows to uncharge resource of
+a process from previously charged cgroup which is migrated to new cgroup,
+even though that is not a primary use case.
+
+Resource pool object is created in following situations.
+(a) User sets the limit and no previous resource pool exist for the device
+of interest for the cgroup.
+(b) No resource limits were configured, but IB/RDMA stack tries to
+charge the resource. So that it correctly uncharge them when applications are
+running without limits and later on when limits are enforced during uncharging,
+otherwise usage count will drop to negative.
+
+Resource pool is destroyed if all the resource limits are set to max and
+it is the last resource getting deallocated.
+
+User should set all the limit to max value if it intents to remove/unconfigure
+the resource pool for a particular device.
+
+IB stack honors limits enforced by the rdma controller. When application
+query about maximum resource limits of IB device, it returns minimum of
+what is configured by user for a given cgroup and what is supported by
+IB device.
+
+Following resources can be accounted by rdma controller.
+ hca_handle Maximum number of HCA Handles
+ hca_object Maximum number of HCA Objects
+
+2. Usage Examples
+-----------------
+
+(a) Configure resource limit:
+echo mlx4_0 hca_handle=2 hca_object=2000 > /sys/fs/cgroup/rdma/1/rdma.max
+echo ocrdma1 hca_handle=3 > /sys/fs/cgroup/rdma/2/rdma.max
+
+(b) Query resource limit:
+cat /sys/fs/cgroup/rdma/2/rdma.max
+#Output:
+mlx4_0 hca_handle=2 hca_object=2000
+ocrdma1 hca_handle=3 hca_object=max
+
+(c) Query current usage:
+cat /sys/fs/cgroup/rdma/2/rdma.current
+#Output:
+mlx4_0 hca_handle=1 hca_object=20
+ocrdma1 hca_handle=1 hca_object=23
+
+(d) Delete resource limit:
+echo echo mlx4_0 hca_handle=max hca_object=max > /sys/fs/cgroup/rdma/1/rdma.max
diff --git a/Documentation/cgroup-v2.txt b/Documentation/cgroup-v2.txt
index 4cc07ce3b8dd..3b8449f8ac7e 100644
--- a/Documentation/cgroup-v2.txt
+++ b/Documentation/cgroup-v2.txt
@@ -47,6 +47,12 @@ CONTENTS
5-3. IO
5-3-1. IO Interface Files
5-3-2. Writeback
+ 5-4. PID
+ 5-4-1. PID Interface Files
+ 5-5. RDMA
+ 5-5-1. RDMA Interface Files
+ 5-6. Misc
+ 5-6-1. perf_event
6. Namespace
6-1. Basics
6-2. The Root and Views
@@ -328,14 +334,12 @@ a process with a non-root euid to migrate a target process into a
cgroup by writing its PID to the "cgroup.procs" file, the following
conditions must be met.
-- The writer's euid must match either uid or suid of the target process.
-
- The writer must have write access to the "cgroup.procs" file.
- The writer must have write access to the "cgroup.procs" file of the
common ancestor of the source and destination cgroups.
-The above three constraints ensure that while a delegatee may migrate
+The above two constraints ensure that while a delegatee may migrate
processes around freely in the delegated sub-hierarchy it can't pull
in from or push out to outside the sub-hierarchy.
@@ -350,10 +354,10 @@ all processes under C0 and C1 belong to U0.
Let's also say U0 wants to write the PID of a process which is
currently in C10 into "C00/cgroup.procs". U0 has write access to the
-file and uid match on the process; however, the common ancestor of the
-source cgroup C10 and the destination cgroup C00 is above the points
-of delegation and U0 would not have write access to its "cgroup.procs"
-files and thus the write will be denied with -EACCES.
+file; however, the common ancestor of the source cgroup C10 and the
+destination cgroup C00 is above the points of delegation and U0 would
+not have write access to its "cgroup.procs" files and thus the write
+will be denied with -EACCES.
2-6. Guidelines
@@ -1119,6 +1123,91 @@ writeback as follows.
vm.dirty[_background]_ratio.
+5-4. PID
+
+The process number controller is used to allow a cgroup to stop any
+new tasks from being fork()'d or clone()'d after a specified limit is
+reached.
+
+The number of tasks in a cgroup can be exhausted in ways which other
+controllers cannot prevent, thus warranting its own controller. For
+example, a fork bomb is likely to exhaust the number of tasks before
+hitting memory restrictions.
+
+Note that PIDs used in this controller refer to TIDs, process IDs as
+used by the kernel.
+
+
+5-4-1. PID Interface Files
+
+ pids.max
+
+ A read-write single value file which exists on non-root cgroups. The
+ default is "max".
+
+ Hard limit of number of processes.
+
+ pids.current
+
+ A read-only single value file which exists on all cgroups.
+
+ The number of processes currently in the cgroup and its descendants.
+
+Organisational operations are not blocked by cgroup policies, so it is
+possible to have pids.current > pids.max. This can be done by either
+setting the limit to be smaller than pids.current, or attaching enough
+processes to the cgroup such that pids.current is larger than
+pids.max. However, it is not possible to violate a cgroup PID policy
+through fork() or clone(). These will return -EAGAIN if the creation
+of a new process would cause a cgroup policy to be violated.
+
+
+5-5. RDMA
+
+The "rdma" controller regulates the distribution and accounting of
+of RDMA resources.
+
+5-5-1. RDMA Interface Files
+
+ rdma.max
+ A readwrite nested-keyed file that exists for all the cgroups
+ except root that describes current configured resource limit
+ for a RDMA/IB device.
+
+ Lines are keyed by device name and are not ordered.
+ Each line contains space separated resource name and its configured
+ limit that can be distributed.
+
+ The following nested keys are defined.
+
+ hca_handle Maximum number of HCA Handles
+ hca_object Maximum number of HCA Objects
+
+ An example for mlx4 and ocrdma device follows.
+
+ mlx4_0 hca_handle=2 hca_object=2000
+ ocrdma1 hca_handle=3 hca_object=max
+
+ rdma.current
+ A read-only file that describes current resource usage.
+ It exists for all the cgroup except root.
+
+ An example for mlx4 and ocrdma device follows.
+
+ mlx4_0 hca_handle=1 hca_object=20
+ ocrdma1 hca_handle=1 hca_object=23
+
+
+5-6. Misc
+
+5-6-1. perf_event
+
+perf_event controller, if not mounted on a legacy hierarchy, is
+automatically enabled on the v2 hierarchy so that perf events can
+always be filtered by cgroup v2 path. The controller can still be
+moved to a legacy hierarchy after v2 hierarchy is populated.
+
+
6. Namespace
6-1. Basics
diff --git a/Documentation/devicetree/bindings/rtc/armada-380-rtc.txt b/Documentation/devicetree/bindings/rtc/armada-380-rtc.txt
index 2eb9d4ee7dc0..c3c9a1226f9a 100644
--- a/Documentation/devicetree/bindings/rtc/armada-380-rtc.txt
+++ b/Documentation/devicetree/bindings/rtc/armada-380-rtc.txt
@@ -1,9 +1,11 @@
-* Real Time Clock of the Armada 38x SoCs
+* Real Time Clock of the Armada 38x/7K/8K SoCs
-RTC controller for the Armada 38x SoCs
+RTC controller for the Armada 38x, 7K and 8K SoCs
Required properties:
-- compatible : Should be "marvell,armada-380-rtc"
+- compatible : Should be one of the following:
+ "marvell,armada-380-rtc" for Armada 38x SoC
+ "marvell,armada-8k-rtc" for Aramda 7K/8K SoCs
- reg: a list of base address and size pairs, one for each entry in
reg-names
- reg names: should contain:
diff --git a/Documentation/devicetree/bindings/rtc/cortina,gemini.txt b/Documentation/devicetree/bindings/rtc/cortina,gemini.txt
new file mode 100644
index 000000000000..4ce4e794ddbb
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/cortina,gemini.txt
@@ -0,0 +1,14 @@
+* Cortina Systems Gemini RTC
+
+Gemini SoC real-time clock.
+
+Required properties:
+- compatible : Should be "cortina,gemini-rtc"
+
+Examples:
+
+rtc@45000000 {
+ compatible = "cortina,gemini-rtc";
+ reg = <0x45000000 0x100>;
+ interrupts = <17 IRQ_TYPE_LEVEL_HIGH>;
+};
diff --git a/Documentation/devicetree/bindings/rtc/imxdi-rtc.txt b/Documentation/devicetree/bindings/rtc/imxdi-rtc.txt
index c9d80d7da141..323cf26374cb 100644
--- a/Documentation/devicetree/bindings/rtc/imxdi-rtc.txt
+++ b/Documentation/devicetree/bindings/rtc/imxdi-rtc.txt
@@ -8,10 +8,13 @@ Required properties:
region.
- interrupts: rtc alarm interrupt
+Optional properties:
+- interrupts: dryice security violation interrupt
+
Example:
rtc@80056000 {
compatible = "fsl,imx53-rtc", "fsl,imx25-rtc";
reg = <0x80056000 2000>;
- interrupts = <29>;
+ interrupts = <29 56>;
};
diff --git a/Documentation/devicetree/bindings/rtc/maxim,ds3231.txt b/Documentation/devicetree/bindings/rtc/maxim,ds3231.txt
index 1ad4c1c2b3b3..85be53a42180 100644
--- a/Documentation/devicetree/bindings/rtc/maxim,ds3231.txt
+++ b/Documentation/devicetree/bindings/rtc/maxim,ds3231.txt
@@ -1,7 +1,8 @@
* Maxim DS3231 Real Time Clock
Required properties:
-see: Documentation/devicetree/bindings/i2c/trivial-admin-guide/devices.rst
+- compatible: Should contain "maxim,ds3231".
+- reg: I2C address for chip.
Optional property:
- #clock-cells: Should be 1.
diff --git a/Documentation/devicetree/bindings/rtc/pcf8563.txt b/Documentation/devicetree/bindings/rtc/pcf8563.txt
index 086c998c5561..36984acbb383 100644
--- a/Documentation/devicetree/bindings/rtc/pcf8563.txt
+++ b/Documentation/devicetree/bindings/rtc/pcf8563.txt
@@ -3,7 +3,8 @@
Philips PCF8563/Epson RTC8564 Real Time Clock
Required properties:
-see: Documentation/devicetree/bindings/i2c/trivial-admin-guide/devices.rst
+- compatible: Should contain "nxp,pcf8563".
+- reg: I2C address for chip.
Optional property:
- #clock-cells: Should be 0.
diff --git a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt
new file mode 100644
index 000000000000..e2837b951237
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt
@@ -0,0 +1,27 @@
+STM32 Real Time Clock
+
+Required properties:
+- compatible: "st,stm32-rtc".
+- reg: address range of rtc register set.
+- clocks: reference to the clock entry ck_rtc.
+- interrupt-parent: phandle for the interrupt controller.
+- interrupts: rtc alarm interrupt.
+- st,syscfg: phandle for pwrcfg, mandatory to disable/enable backup domain
+ (RTC registers) write protection.
+
+Optional properties (to override default ck_rtc parent clock):
+- assigned-clocks: reference to the ck_rtc clock entry.
+- assigned-clock-parents: phandle of the new parent clock of ck_rtc.
+
+Example:
+
+ rtc: rtc@40002800 {
+ compatible = "st,stm32-rtc";
+ reg = <0x40002800 0x400>;
+ clocks = <&rcc 1 CLK_RTC>;
+ assigned-clocks = <&rcc 1 CLK_RTC>;
+ assigned-clock-parents = <&rcc 1 CLK_LSE>;
+ interrupt-parent = <&exti>;
+ interrupts = <17 1>;
+ st,syscfg = <&pwrcfg>;
+ };
diff --git a/Documentation/devicetree/bindings/rtc/sun6i-rtc.txt b/Documentation/devicetree/bindings/rtc/sun6i-rtc.txt
index f007e428a1ab..945934918b71 100644
--- a/Documentation/devicetree/bindings/rtc/sun6i-rtc.txt
+++ b/Documentation/devicetree/bindings/rtc/sun6i-rtc.txt
@@ -8,10 +8,20 @@ Required properties:
memory mapped region.
- interrupts : IRQ lines for the RTC alarm 0 and alarm 1, in that order.
+Required properties for new device trees
+- clocks : phandle to the 32kHz external oscillator
+- clock-output-names : name of the LOSC clock created
+- #clock-cells : must be equals to 1. The RTC provides two clocks: the
+ LOSC and its external output, with index 0 and 1
+ respectively.
+
Example:
rtc: rtc@01f00000 {
compatible = "allwinner,sun6i-a31-rtc";
reg = <0x01f00000 0x54>;
interrupts = <0 40 4>, <0 41 4>;
+ clock-output-names = "osc32k";
+ clocks = <&ext_osc32k>;
+ #clock-cells = <1>;
};
diff --git a/Documentation/static-keys.txt b/Documentation/static-keys.txt
index ea8d7b4e53f0..32a25fad0c1b 100644
--- a/Documentation/static-keys.txt
+++ b/Documentation/static-keys.txt
@@ -155,7 +155,9 @@ or:
There are a few functions and macros that architectures must implement in order
to take advantage of this optimization. If there is no architecture support, we
-simply fall back to a traditional, load, test, and jump sequence.
+simply fall back to a traditional, load, test, and jump sequence. Also, the
+struct jump_entry table must be at least 4-byte aligned because the
+static_key->entry field makes use of the two least significant bits.
* select HAVE_ARCH_JUMP_LABEL, see: arch/x86/Kconfig